Head-protecting shells and the like articles obtained through deformation of sheets of synthetic material



3,075,200 HELLS AND THE LIKE ARTICLES OBTAINED THROUGH DEFORMATION OFSHEETS 0F SYNTHETIC MATERIAL Filed Feb. 18, 1960 1963 JEAN-PHILIPPECROUZET HEAD-PROTECTING S 2 Sheets-Sheet 1 Jan. 29, 1963 JEAN-PHILIPPECROUZET 3,075,200 HEAD-PROTECTING SHELLS AND THE LIKE ARTICLES OBTAINEDTHROUGH DEFORMATION 0F SHEETS 0F 'SYNTHETIC MATERIAL Filed Feb. 18, 19602 Sheets-Sheet 2 iifififihh Patented Jan. 29, 1963 3,075,260HEAD-PRGTECTHVG SHELLS AND THE LIKE AR- TZCLES GBTAINED THRGUGHDEFGRMATEQN F SEEETS 0F SYNTHETIC MATERIAL .iean-Pliiiippe Crcuzet,123Blvd. Malesherhes, Paris, France Filed Feb. 18, 196i), Ser. No. 9,559Claims priority, application France Get. 8, 1959 3 Claims. (Cl. 2--3) Myinvention has for its object articles made out of sheets of semi-rigidsynthetic material, such as that sold under the registered trade nameRhodoid, or the like, said articles being obtained through deformationof previously cut sheets and the shaping of which is obtained throughbending and twisting.

My invention is applicable chiefly to the shells adapted to form ahead-gear or helmet protecting the wearers head against cold andunclement weather, said helmet enclosing the wearers head and engagingthe Wearers shoulders as described in my copending application claimingpriority of my French patent filed on December 18, 1956 and publishedunder No. 1,163,519 (U.S. Ser. No. 648,252 and 732,402, now US. PatentNumbers 2,988,749 and 2,939,049, respectively).

The articles obtained in this manner show the drawback of being verybrittle when subjected to cold. As a matter of fact, the thickness ofthe sheet used is limited, so as to provide the yieldingness ensuring asufiicient bending capacity, said thickness being, for instance, equalto 7 of a mm. But, it is found that under the action of the shockstransmitted to such a sheet, either directly or indirectly, the inneredges of the reentering sections of the cut out outline of the sheet maylead to initiating cracks, since the inner strains produced by thedeformation are maximum along said edges.

The free edges of the deformed semi-rigid sheets, such, for instance, asthose surrounding the openings of the shell are also liable to crack andthe same is the case for the sections weakened by rivets and which may,under the action of the tensioning stresses transmitted to them, breakopen the sheet between its edge and a rivet or between successiverivets.

Now, my invention has for its object to glue or otherwise secure overthe semi-rigid sheet before it is deformed reinforcing strips extendingalong the edges of the cut out parts forming a reentering angle in theoutline of the sheet to be shaped; each reinforcing strip is constitutedby a layer of synthetic material, the thickness of which issubstantially equal to that of the actual sheet, while the breadth ofeach reinforcement is at a maximum at a point in registry with the pointof the cut out part showing a minimum radius of curvature, such as, forinstance, the bottom of the cut out parts forming a reentering angle.The breadth of said reinforcements is variable and ranges substantiallybetween 6 and 12 mm. According to a further feature of my invention,these reinforcements or supplementary reinforcements surround at leastthe portions of the edges of the rivet holes subjected to the higheststraining and they extend also at least partly along the free deformededges of the sheet.

I have found that the articles made of a shaped semirigid sheet securedby rivets, chiefly a sheet of the material sold under theabove-mentioned registered trademark Rhodoid and including suchreinforcements, are mechanically very resistant and do not break underthe action of shocks.

In the case of rivet holes, the reinforcements, even if they surroundonly partly said rivet holes, increase the rigidity of the part of thehole edge which is not reinforced and absorb the stresses transmitted tothe latter and to which said non-reinforced part is thus subjected.

My invention has also for its object, by way of novel articles ofmanufacture, the articles made of semi'rigid sheets of syntheticmaterial and, chiefly, head-gear shells serving as helmets forprotection against cold Weather and including reinforcements constitutedby a layer of syn.- thetic material glued chiefly along the edges of thereentering angles formed along the outline cut in the sheet forming thearticle considered as also along the parts of the sheet which areweakened and its free deformed edges.

I will now describe an embodiment of my invention as applied to aprotecting head-gear shell, reference being made to the accompanyingdrawings, wherein:

PEG. 1 is a perspective view of the head-gear shell provided withreinforcements.

FIG. 2 is a View from above, on a reduced scale, of the sheet of Rhodoidmaterial provided with its reinforcements before its final deformationinto the shape illustrated in FIG. 1.

The protecting shell or helmet illustrated in FIG. 1 forms a transparentcasing surrounding the wearers head and engaging, through its lower openend, the wearers shoulders and the upper part of his back and of hischest, the arrangement including furthermore in its front section ports11 which allow the outer air required for breathing purposes to enterthe helmet.

The arrangement is held in position by elastic bands 12 adapted to passunderneath the wearers armpits, said bands terminating with rings 13engaging hooks 14 secured at 15 to the shell in the vicinity of itslower edge along the lateral front and rear portions of the latter.

The shell illustrated, of a generally ovoid shape, is obtained startingfrom a semi-rigid sheet of transparent synthetic material, such as thatsold under the registered trademark Rhodoid, the thickness of whichsheet is equal to about 9 of a mm. Each sheet is cut out so as toproduce a surface 16 adapted to form the front of the shell togetherwith the adjacent sections of the side wall. The lower part of the frontsurface is turned inwardly, as provided by the cuts 17 which allow anoverlapping of the edges of the cuts which are held in position throughthe introduction in the perforations 18 of rivets or the like securingmeans. The aeratingports 11 are provided in said surface 16 in thevicinity of the cuts 17 and betweenthe latter. I

In prolongation of the central part of said surface 16 and opposite cuts17, the sheet is cut and forms a surface 19 of a generally hexagonalshape, the deformation of which provides a connecting surface betweenthe front lateral surface 16 and a surface 20 forming the parietalsection of the shell. The surface 21} is substantially rectangular. Theassembly of the surface 19 with the upper edge of the surface 16 isobtained through registration between the openings 21 through whichrivets or the like extend to 'hold the surfaces fast together.Similarly, the

assembly between the rear oblique edges of the surface 19 and the fronttransverse edges of the parietal surface 29 is provided through openings22 and corresponding securing means.

The sides of the parietal surface 21} are connected with the lateralouter sections of the surface 16 through securing thereof together inregistry with the openings 23 which are caused to register in saidsurfaces. It is however obvious, from a mechanical standpoint, that thissecuring together of the surfaces provides only a pseudocylindricaldeformation of the elements, which leads to only negligible internalstresses with reference to the pseudo-spherical deformations arisingupon registration of the openings 21 and of the openings 22 forinsertion of securing means therethrough.

In its rear section, the shell is made in a similar manner and theparietal surface 29 extends into a surface 24 in the shape of anirregular hexagon which, in its turn, is rigid with a further surface 25adapted to form the rear portion of the shell. The surface 24 issubjected, after securing of its front edges through the openings 25with the rear edges of the parietal surface 29 and through the openings27 of its rear edges with the cooperating edges of the rear surface 25,to a pseudo-spherical deformation producing a substantial innerstraining. In conradistinction, the connections through rivets or thelike 28 extending in cooperating perforations in the lateral sections ofthe parietal surface 24} and the front lateral edges of the rear surface25 and through the rivets passing through the openings 29 in the rearlateral sections of the front surface 16 and the lateral sections of therear surface 25 produce only pseudo-cylindrical deformations and,consequently, reduced internal stresses.

The internal strains appearing in the surfaces thus constituted are at amaximum at the apices of the cuts providing for a connection between apseudo-spherical surface and another pseudo-spherical surface having tworadii of curvature or a pseudo-cylindrical surface having a singleradius of curvature.

In the embodiment described, the brittleness ascribable to such internalstrains results in the formation of initiating breaks at the bottom ofthe cuts 17, on the one hand and, on the other hand, in the bottom ofthe angle separating the surface 19 from the other surfaces 16 and 2tand the surface 24 from the surfaces 20 and 25.

In order to cut out such initiating breaks and the damage which mayoccur in the case of fortuitous shocks, there are provided, inconformity with my invention, reinforcements constituted by strips cutin a semi-rigid sheet of plastic material, such the Rhodoid referred tohereinabove, having a thickness of about 7 of a mm., said strips beingglued to outwardly facing areas of the main sheet.

At the inner end of each cut 17 is thus glued an arcuate strip 3Q,while, at the apex of the reentering angles between the surfaces 19 and16 or 20, on the one hand, and between the surfaces 20 and 24 or 25, onthe other hand, reinforcing strips 31 are positioned. The breadth of thestrips 31 varies between 6 and 12 mm. and it reaches a maximum inregistry with the apices of the corresponding angles. Said reinforcingstrips 31 surround also, at least partly, on the side of the sheet withwhich they are rigid, the openings or perforations 21, 22, 26 and 27adapted to be engaged by rivets or the like connecting means. Similarreinforcements in the shape of strips 32 extend also along the lowerlateral edges of the front section, or surface 16.

After the final assembly, two reinforcements 34 (FIG. 1) are gluedinwardly and along the lower edge in registry with the line ofconnection between the front and rear surfaces.

As clearly shown in FIG. 1, the reinforcements, as also the surfacesrigid therewith, are subjected, upon assembly, to an intense mechanicaldeformation, chieiiy in registry with their broadest cross-section, butthe considerable thickness obtained through their superposition over theactual main sheet prevents the initiation of cracks and breaks and allthe more so by reason of the superposition and gluing together ofindependent layers. It should be remarked that such an extra thickness,if extended throughout the surface of the main sheet, would prevent thepseudo-spherical and pseudo-cylindrical deformations inherent to theshaping of the article.

Of course, the embodiment disclosed by way of example is capable ofvarious modifications within the scope of the accompanying claims, whilethe method described for producing a helmet or head-gear is applicable,as well, within the scope of said claims, to various types of articles.

What I claim is:

1. A head-protecting helmet to encompass the head comprising anelongated sheet of semi-rigid synthetic material including a firstsection defining a substantially rectangular configuration, a secondsection defining a substantially hexagonal configuration, a thirdsection defining a substantially rectangular configuration, said secondsection being interposed between said first and third sections alongcommon sides therebetween and having reentering angles between the freesides of said second section and outward extensions of the common sidesof the first and third sections, a fourth section defining asubstantially hexagonai configuration, a fifth section de lining asubstantially rectangular configuration, said fourth section beinginterposed between said third and fifth sections along common sidestherebetween and having rcentering angles between the free sides of saidfourth section and outward exlensions of the common sides of the thirdand fifth sections, reinforcing strips of semi-rigid material having athickness substantially equal to that of said elongated sheet disposedon the surface thereof surrounding the apex of each of said re-enteringangles and along each free side and outward extension thereof toreinforce these portions when and after the thus constituted elongatedsheet is formed into saidhead-protecting helmet, means for maintainingsaid reinforcing strips on said elongated sheet, and fastening meansdisposed along the edges of the sides of each of said sections to fasenthese edges together in overlapping relation to thereby provide saidhead-protecting helmet.

2. A head-protecting helmet according to claim 1 in which said means formaintaining said reinforcing strips on said elongated sheet compriseglue.

3. A head protecting helmet according to claim 1 in which said firstsection has disposed in the side opposite to the common side thereof atleast two parallel cuts that are substantially perpendicular to theopposite side, said reinforcing strips being disposed at the inward endof each cut and said fastening means being disposed along the edges ofeach cut to maintain the edges in overlapping relation when the helmetis formed to provide an inwardly turned portion of said first section.

References Cited in the file of this patent UNITED STATES PATENTS1,576,023 Barberis Mar. 9, 1926 1,795,866 King Mar. 10, 1931 2,289,858Angrave July 14, 1942 2,620,477 Ackerman Dec. 9, 1952 FOREIGN PATENTS798,277 Great Britain July 16, &

1. A HEAD-PROTECTING HELMET TO ENCOMPASS THE HEAD COMPRISING AN ELONGATED SHEET OF SEMI-RIGID SYNTHETIC MATERIAL INCLUDING A FIRST SECTION DEFINING A SUBSTANTIALLY RECTANGULAR CONFIGURATION, A SECOND SECTION DEFINING A SUBSTANTIALLY HEXAGONAL CONFIGURATION, A THIRD SECTION DEFINING A SUBSTANTIALLY RECTANGULAR CONFIGURATION, SAID SECOND SECTION BEING INTERPOSED BETWEEN SAID FIRST AND THIRD SECTIONS ALONG COMMON SIDES THEREBETWEEN AND HAVING REENTERING ANGLES BETWEEN THE FREE SIDES OF SAID SECOND SECTION AND OUTWARD EXTENSIONS OF THE COMMON SIDES OF THE FIRST AND THIRD SECTIONS, A FOURTH SECTION DEFINING A SUBSTANTIALLY HEXAGONAL CONFIGURATION, A FIFTH SECTION DEFINING A SUBSTANTIALLY RECTANGULAR CONFIGURATION, SAID FOURTH SECTION BEING INTERPOSED BETWEEN SAID THIRD AND FIFTH SECTIONS ALONG COMMON SIDES THEREBETWEEN AND HAVING REENTERING ANGLES BETWEEN THE FREE SIDES OF SAID FOURTH SECTION AND OUTWARD EXTENSIONS OF THE COMMON SIDES OF THE THIRD AND FIFTH SECTIONS, REINFORCING STRIPS OF SEMI-RIGID MATERIAL HAVING A THICKNESS SUBSTANTIALLY EQUAL TO THAT OF SAID ELONGATED SHEET DISPOSED ON THE SURFACE THEREOF SURROUNDING THE APEX OF EACH OF SAID RE-ENTERING ANGLES AND ALONG EACH FREE SIDE AND OUTWARD EXTENSION THEREOF TO REINFORCE THESE PORTIONS WHEN AND AFTER THE THUS CONSTI- 